factor(x^4+1) and partfrac(1/(x^4+1))

[Joe Horn]

(10-22-2019 09:15 AM)rombva Wrote:  I don't want to get a factorization result over the complex field. The polynomial x^4+1 may be rewriten as a product of polynomials over the field of reals (for example, HP 50g can factorize it). What's wrong with HP Prime's factorization in the real mode in this case?

Check your CAS settings. Near the bottom of the first page, in the left column, the second item is "Use square roots to factor polynomials". When that's turned on (the default setting), it yields the result you want:



EDIT: Oops! You're right: The recent publicly released firmware versions return x^4+1 unchanged. The above screen shot was apparently from a different firmware version, possibly a beta version which didn't say "BETA" in the top corner. My mistake. Sorry!